Rat Study Suggests Gadolinium Injections May Leave Deposits in Brain

Published on July 16, 2018 by Sandy Liebhard

A recent study involving rats is adding to concerns that toxic gadolinium deposits may accumulate in the body – specifically the brain – following the administration of certain MRI contrast dyes.

FDA Gadolinium Retention Warning

Gadolinium-based MRI contrast dyes are indicated to improve the visibility of organs, tumors, and blood vessels on imaging scans.

In 2007, the labels for these agents were updated to warn against their use in patients with impaired kidneys, after they were linked to a rare and life-threatening disease called nephrogenic systemic fibrosis, or NSF. Nevertheless, it has long been assumed that, when injected into patients with normal renal function, most gadolinium contained in these  dyes would be filtered through the kidneys and passed from the body via urine.

In recent years, however, a growing body of evidence has suggested that this is not actually the case. In December 2017, the U.S. Food & Drug Administration (FDA) even warned that gadolinium deposits could be retained in the body for weeks, months, and even years following an MRI and ordered the manufacturers of such agents to add new warnings to their product labels regarding the possibility of gadolinium retention.

The warning applied to all gadolinium MRI agents currently approved for use in the United States, including:

• Dotarem (Gadoterate meglumine)
• Eovist (Gadoxetate disodium)
• Gadavist (Gadobutrol)
• Magnevist (Gadopentetate Dimeglumine)
• MultiHance (Gadobenate Dimeglumine)
• Omniscan (Gadodiamide)
• Optimark (Gadoversetamide)
• Prohance (Godoteridol)

The FDA also ordered the drugs’ makers to conduct studies in both humans and animals to better evaluate the safety of these agents.

What did this Latest Study Find?

For this study, French and German researchers administered 20 daily gadolinium injections to rats with impaired kidney function. Control rats were injected with saline. The deep cerebellum and the choroid plexus sections of the animals’ brains were examined via an electron microscope 1 month after the last injection.

The examinations revealed that tissue from animals injected with Omniscan and MultiHance contained spherical gadolinium deposits that resembled “sea urchins” and were rich in phosphates.

Of note, the study authors found no such deposits among rats injected with Dotarem.

Gadolinium MRI Lawsuits

The manufacturers of gadolinium-based MRI contrast dyes have already settled some lawsuits involving NSF.

However, in recent years, they have faced a growing number of legal claims filed on behalf of patients with normal kidney function who are alleged to have experienced ill health affects due to gadolinium retention after an MRI.

Plaintiffs pursuing these MRI contrast agent lawsuits claim to be suffering from “Gadolinium Deposition Disease,” symptoms of which are said to include:

• Intense burning of the skin and skin substrate
• Intense boring pain in bones or joints
• Brain fog or mental confusion
• Muscle vibrations, pins and needles sensation
• Headache
• Thickening, discoloration, pain in the skin or skin substrate of the distal arms and legs

Plaintiffs further claim that the manufacturers of MRI contrast agents have long been aware of the potential for gadolinium retention. Yet they have failed to provide doctors and patients with adequate warnings regarding this risk.